Manufacture of portland cement



Patented May 22, 1934 UNITED STATES MANUFACTURE OF PORTLAND CEMENTMartin Newcomer, Woodbridge, N. J., and Vincent Kay Newcomer,Independence, M0.

N Drawing. Application June 7, 1933, Serial No. 674,714

2 Claims.

In the manufacture of Portland cement the cement raw materials arepassed through a rotary kiln in which they are subjected successively toa drying operation, a calcining operation and a 5 sintering operationunder the influence of the intense heat of combustion of fuel which issupplied at the end of the kiln at whch the resulting clinker isdischarged. In the succession of operations at some point in thesintering zone of the kiln the sintered material begins to adhere to thewall of the kiln and there is gradually built up on the wall of the kilna ring of sintered material which eventually, if the formation isallowed to continue, reduces greatly the capacity 5 of the kiln. Suchrings difier, under different conditions, in type, shape and chemicalanalysis. Sometimes they are hard, as in the case of what are calledcoal rings, which form near the discharge end of the kiln. Others may belong and somewhat soft and sticky, but at the same time tough. Torestore the production capacity of the kiln the ring must be broken downand removed. To stop the kiln for this purpose involves production loss,increased fuel cost in reheating, and often damage to the refractorylining of the kiln. The usual practice, therefore, is to attempt tobreak down the ring by successive discharges into it of solidprojectiles from a suitable type of gun, the intention being in thatmanner to cut gaps in the ring with the hope that eventually theremaining portions of the ring will break loose and move onward throughthe kiln to the point of discharge. This procedure is not only uncertainin results but consumes much time because many shots are necessary andthe gunner must be protected from the intense heat at the firing point.

It has been the object of the present invention to make it possible tobreak down the ring more completely and expeditiously and therefore toavoid the serious production loss incident to the methods heretoforeemployed and in accordance with the invention the heat of the ringitself is taken advantage of to effect the explosion of a projectile,loaded with an explosive charge, fired into the ring from a suitablegun. It has been found that the ring can be broken down by a fewexplosions, the explosive charge within each projectile being soregulated as to break down the ring without injury to the refractorylining of the kiln. It will be obvious that the character of theexplosive charge can be varied to suit conditions. It might be formed ofa suitable explosive, such as black powder, for example, or it mighteven be formed of water, the heat of the ring being sufficient to setoff the powder or to vaporize the water so quickly as to produce anexplosive effect.

Each projectile is formed as a hollow shell of iron or brass or othersuitable material in shape like a bullet and adapted to have enclosedwithin it a suitable quantity of the explosive employed. It is of suchdiameter as to permit it to be discharged from a gun of suitablecalibre. The cavity of the projectile has enclosed within it the properexplosive charge, Whether of powder, or any other ordinary explosive, orwater, or any other substance capable of exerting great gaseous pressurein the shell when heated to a temperature such as that attained by thering, which may be from 2000 F. to 2750 F. The projectile is propelledby a charge sufficient only to drive it into the ring where it remainsuntil the heat penetrates the shell and explodes the charge within it.The explosion of the shell has a shattering effect on the material ofthe ring. It will be understood that the time of flight of theprojectile from the gun to the ring is so brief that the shell will notbe raised, in the heated atmosphere of the kiln, to a degree sufficientto cause the shell to explode.

We claim as our invention:

1. The method of breaking down a ring of sintered material on the wallof a rotary cement kiln while the same is in a highly heated conditionwhich consists in introducing an explosive charge within the substanceof the ring and exploding the same by the heat of the ring.

2. The method of breaking down a ring of sintered material on the wallof a rotary cement kiln while the same is in a highly heated conditionwhich consists in introducing into the substance of the ring a hollowbody charged with a substance susceptible of being exploded by the heatof the ring.

MARTIN NEWCOMER. VINCENT KAY NEWCOMER.

